Function bfs

javascript/0022-generate-parentheses.js:64–88

(n, combos = [])

var generateParenthesis = (n) => bfs(n);

const bfs = (n, combos = []) => {
    const queue = new Queue([['', 0, 0]]);

    while (!queue.isEmpty()) {
        /* Time O(2^N) */
        const [str, open, close] = queue.dequeue();

        const isBaseCase = open === n && close === n;
        if (isBaseCase) {
            combos.push(str); /* Space O(N) */

            continue;
        }

        const isOpen = open < n;
        if (isOpen)
            queue.enqueue([`${str}(`, open + 1, close]); /* Space O(2^N) */

        const isClose = close < open;
        if (isClose)
            queue.enqueue([`${str})`, open, close + 1]); /* Space O(2^N) */
    }

    return combos;
};

/**
 * DFS